Effects of "anorexia" in appetitive and consummatory behavior.

Abstract

In order to assess the effects of anorexigenic agents on appetitive and consummatory behavior, rats were given sweetened milk either in a bottle or by infusion through an intraoral cannula. In the first experiment, amphetamine (AMP; 0, 0.25, 0.5, and 1 mg/kg) had no effect on the intake of cannula-fed rats but suppressed the intake of bottle-fed rats at the highest two doses. Although increased activity was observed at the highest dose, bottle-fed rats drank less than cannula-fed rats at each dose of the drug. Fenfluramine (FEN; 0, 2.5, 5, and 10 mg/kg) produced a dose-dependent decrease in intake with both methods of feeding, but the effect was greater in bottle-fed rats. Although FEN had marked sedative effects at the highest two doses, bottle-fed rats drank less than cannula-fed rats at each dose of the drug. In a second experiment, cannula- and bottle-fed rats were given milk adulterated with various concentrations of quinine hydrochloride (QHCl; 0, 0.0025, 0.005, 0.01, and 0.02%). QHCl had no effect on the intake of cannula-fed rats but decreased the intake of bottle-fed rats at the highest two concentrations. In a final experiment, the effect of AMP (1 mg/kg) was assessed in a conditioned aversion paradigm. Rats were given four conditioning trials in which access to a 0.1% sodium saccharin solution was followed by an injection of AMP. Again, bottle-fed rats showed greater suppression of intake than cannula-fed rats. Taken together, these results demonstrate that anorexigenic drugs affect appetitive behavior more than consummatory behavior. The implications of these findings for understanding the mechanism of behavioral tolerance are discussed.

Evidence that Release of Dopamine in the Brain is Involved in the Inhibitory Effect of Cholecystokinin Octapeptide on Ingestion of Intraorally Administered Sucrose in Male Rats

“…With these procedures the effects of amphetamine were virtually identical to those reported by Wolgin et a/. (6), i.e. a strong effect on pellet intake and.…”

The Neuroanatomical Axis for Control of Energy Balance

“…Thus, intraoral intake is sensitive to the prototypical physiological manipulations (e.g., deprivation, preloading) and a variety of taste and postingestive treatments (59,97,160). Several pharmacological treatments, however, affect meal size in standard tests but affect intraoral intake either weakly or not at all (163,202). A discussion of the methodological contrasts relating to appetitive and consummatory phases of intake control is beyond the scope of this review.…”

The effects of dose and repeated administration on the longer-term hypophagia produced by amphetamine in rats

“…In rats, amphetamine doses above 0.25 mg/kg are required to reduce short-term intake (Colle and Wise, 1988; Gilbert and Cooper, 1985; Towell et al, 1988; Wolgin et al, 1988). Generally, when amphetamine is repeatedly administered tolerance to reduced short-term intake is observed (Milloy and Glick, 1976; Poulos et al, 1981; Salisbury and Wolgin, 1985).…”

“…Generally, when amphetamine is repeatedly administered tolerance to reduced short-term intake is observed (Milloy and Glick, 1976; Poulos et al, 1981; Salisbury and Wolgin, 1985). Reduced short-term intake and tolerance have been ascribed to a variety of processes including changes in appetitive or consummatory behavior (Wolgin et al, 1988), elicitation and suppression of stereotyped behaviors that interfere with food intake (Salisbury and Wolgin, 1985; Wolgin et al, 1987), and shifts in hunger or in body weight set point (Caul et al, 1988; Wolgin, 1983). Tolerance has also been ascribed to the development of Pavlovian compensatory responses (Caul et al, 1988; Poulos et al, 1981; Wolgin, 1983).…”